Zur Beschreibung weitreichender Kopplungen mittels der Pars-Orbital-Methode / Long-range Couplings, Methyl-substituted Coumarines and Carbostyriles, Pars-Orbital and Pertur-bational Calculations

Abstract

An attempt has been made to correlate long range couplings in a series of methyl-substituted coumarines and carbostyriles with the character orders of the corresponding propen- and methyl-butadienfragments. In the case that these character orders exceed a threshold value of about 0.700, relatively large long-range couplings are to be expected. In addition calculations of these couplings by the finite perturbation approach have been performed.